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The sedimentary sequence of La Narce du Béage Basin is one of the few natural archives covering the last 18 ka cal. BP in the French Massif Central. This paper focuses on the palaeoecological reconstruction of environmental and climatic changes affecting this shallow periglacial lake from the Late-Glacial to the Early Holocene. After field surveys and geophysical mapping, two cores (cores A and D) were extracted and dated. Plant macrofossils, pollen, non-pollen palynomorphs (NPPs) and diatom assemblages were compared within the cores to study vegetation, temperature, pH, water level and ice cover changes through time. During the Oldest Dryas (18–14.75 ka cal. BP), climatic conditions were the coldest with a short ice-free season allowing the development of periphytic diatoms only (ecologically comparable to Arctic ones). A cold and dry steppe landscape – exposed to severe erosion – comprised an herbaceous and shrub flora (e.g. Artemisia , Chenopodiaceae, Helianthemum, Ephedra, Hippophaë, Juniperus). Animal presence is suggested by coprophilous fungi. Periphytic diatoms and allochtonous pollen (Cedrus) underline windy conditions, and the possible erosion of neo-formed soils. Then, during the Bølling-Allerød interstadial (14.75–12.7 ka cal. BP), the ice-free season increased and some trees/shrubs (Salix, Betula and Juniperus) established locally within open grasslands. During the Younger Dryas (12.7–11.7 ka cal. BP) cooler conditions favoured steppe taxa again (Helianthemum, Achillea, Artemisia , Caryophyllaceae, Ranunculaceae) and erosion increased. The ice cover on the lake prevailed even if the conditions were not as cold as during the Oldest Dryas. During the Preboreal (11.7–10 ka cal. BP) Isoëtes echinospora and I. lacustris developed in the eulittoral zone of the lake, which was surrounded by a swamp forest (with Betula nana and B. pubescens). Pinus sylvestris, Betula pendula, Corylus avellana and trees from the Quercetum mixtum rapidly established in the uplands. Occurrences of Gaeumannomyces and Xylomyces fungi – both phytopathogens on broadleaved trees – and decreasing herb values indirectly hint at a close forest canopy. At the beginning of the Boreal (10 ka cal. BP), aquatic and semi-aquatic taxa developed on open water due to longer ice-free seasons (diatoms, micro-algae, Alisma plantago-aquatica, Potamogeton, Typha). The final terrestrialization towards a mire occurred as a consequence of the Holocene warming and related to water chemistry changes (acidification, eutrophication). • During the last deglaciation, a very shallow lake established as demonstrated by palaeoecological data, such as epiphytic diatoms, living on rocks. • Late-Glacial steppe landscape with severe erosion, open grassland and possible mega-herbivore presence. Arctic-like conditions. • Development of shrubs or trees during the Bølling-Allerød interstadial and reduced ice-free season. • Dry and cold conditions persisted from the Younger Dryas to the Early Preboreal. Oligotrophic flora (Isoetids) established in the eulittoral zone. • During the post-glacial warming, the lake tended to acidify. Peat flora and organic matter accumulated and led to the terrestrialization of the lake. [ABSTRACT FROM AUTHOR]

Daily insolation at a given latitude is often used in the explanation of the long-term variations of paleoclimate records. However, the length of astronomical seasons, which has been paid less attention, could also be important. This paper provides an original calculation of the length of these seasons using the eccentric anomaly. The past and future long-term variations as well as the spectral characteristics of the length of astronomical seasons, of the total and average insolation over the astronomical seasons and of the caloric insolation are shown and compared. The length of astronomical seasons is only a function of climatic precession. The total irradiation for a given latitude and an astronomical season is mainly a function of obliquity except that it is mainly a function of eccentricity in a latitudinal band that is season dependent and from where the phase between obliquity and total irradiation reverses (e.g. ∼11.5°N for the astronomical northern hemisphere summer half-year). The spectral characteristic of the mean insolation over the astronomical summer half-year varies in latitude and time. It contains stronger obliquity signal in high latitudes than in low latitudes, but the obliquity signal already gets very weak at 45°N/S leaving the dominance of climatic precession between 45°N and 45°S. The variation of the mean summer half-year insolation over the last 1 Ma is characterized by a Mid-Brunhes transition at ∼450 ka BP, with a dominant role of climatic precession at all latitudes before ∼450 ka BP but significantly enhanced role of obliquity in high latitudes after this time. The simultaneous weakening of the variations of climatic precession and obliquity around 800 ka ago, a time corresponding to the Mid-Pleistocene Transition, leads to weak variations in both total and mean seasonal insolation. The insolation of a specific case, the Holocene, is finally discussed. Depending on the sensitivity to different types of insolation, different climate variables and regions could show different evolution and trend during the Holocene. • An original calculation of the length of the astronomical seasons is provided. • Precession and obliquity contribute differently to the length of astronomical seasons and to different insolation metrics. • Distinctive variations of total and mean seasonal insolation characterize the Mid-Brunhes and Mid-Pleistocene transitions. • Different insolation metrics display different trend over the Holocene. [ABSTRACT FROM AUTHOR]

This paper explores how significant are the ecological and climatic variables to influence the stable isotopes of guanacos. Lama guanicoe bone collagen carbon and nitrogen stable isotope ratios are assumed as a macro regional average value in west Argentina, mostly as a baseline to model archaeological human diet. If stable isotopes on mammals reflex ecology and climate, we need to know how those variables influence mammals bone stable isotope ratio. This paper analyses the 13C/12C and 15 N/14N ratio on bone collagen on 122 guanacos from Northwest Patagonia during the Holocene. The results confirm significant variation in both isotopes between Monte and Andean-Patagonian specimens. Guanacos from Monte shows higher δ13C and δ15N than those from Andean-Patagonian. Temporal trends indicate variation through Holocene but this variation is not spatially homogeneous. In this paper we suggest that Medieval Climatic Anomaly had stronger effect in Monte desert than in Patagonia desert, generating driest and/or hottest conditions between 1250 and 600 years BP. Those variations need to be considered to reconstruct human diet at least during the second part of the Holocene. [ABSTRACT FROM AUTHOR]

Coastal wetlands provide valuable ecosystem services and understanding their response to past climatic changes may help predict their possible future responses. In this paper, we obtained records of pollen, algae, sediment grain-size, and other environmental proxies, from a late Holocene sediment core (CFD-E) from the Caofeidian area, on the northwest coast of the Bay of Bohai, China. Our results indicate three major stages of environmental change. During Stage I (3500–2800 cal yr BP), arboreal pollen content was high (mostly >60%), especially for Pinus and Quercus , and the PCA sample scores on Axis 1 were negative indicating that regional vegetation was temperate broadleaved forest and the climate was wet. During Stage II (2800–2350 cal yr BP), the arboreal pollen content decreased substantially (mostly <40%), and the PCA Axis 1 sample scores were positive indicating a decrease in forest vegetation, grassland expansion, and a drier climate. During Stage III (2350–1400 cal yr BP), the arboreal pollen content increased again (mostly >40%), although it remained lower than during Stage I, indicating that forests expanded under a relatively humid climate while the wetland area decreased slightly. Our results also record the 2.8 ka and 2.4 ka events of monsoon weakening, which were characterized by increases in herbaceous pollen (indicating grassland expansion) and the drying of the regional climate. There are several differences in the regional expression of these two climatic events. During the 2.4 ka event, Chenopodiaceae pollen increased substantially (average of 42.0%), indicating the expansion of halophytes; whereas during the 2.8 ka event, an increase in Artemisia indicates the occurrence of a dry climate throughout the region. We suggest that the aridity during the 2.8 ka event was triggered by decreased solar activity and the resulting changes in the El Niño-Southern Oscillation, which weakened the East Asian summer monsoon. However, we suggest that the 2.4 ka event was driven by the weakening of the Atlantic Meridional Overturning Circulation. • Significant increase in halophytic vegetation during 3500–1400 cal yr BP • The 2.8 ka and 2.4 ka events were characterized by climate drying lasting ∼150 years. • During these two events the area of forest decreased and grassland expanded. [ABSTRACT FROM AUTHOR]

• A proxy based on mass movements for assessing climate change was proposed. • The periodicity of mass movements conforms to the changing patterns of traditional climate proxies. • Climate change determines the spatial and temporal distribution of mass movements. The spatial and temporal distribution, as well as the formation and evolution of mass movements in the Qinghai-Tibet Plateau orogenic belt, have been extensively discussed. We gathered research papers focusing on the ages of Quaternary residual deposits associated with mass movements in the surrounding orogenic belts of the Qinghai-Tibet Plateau. A total of 172 large-scale typical deposits and their ages were analyzed to explore the primary driving mechanisms behind mass movements in the Qinghai-Tibet Plateau. As these deposits were collected from diverse geological environments and the ages primarily concentrated in the Late Pleistocene and Holocene periods, we categorized mass movements with ages younger than 140 ka into three distinct regional climate systems: the Indian Summer Monsoon, the East Asian Summer Monsoon, and the Westerlies. The relationship between the emergence of mass movements and climate change was thoroughly investigated. Our research indicates that mass movements can serve as a reliable proxy for indicating climate change. The cycles of mass movements are closely synchronized with the warm and cold alternations of regional climates, holding significant importance in reshaping the environmental evolutionary history. We propose that the extensive mass movements in the Qinghai-Tibet Plateau are primarily driven by periodic climate variations, although they may not exhibit a perfect one-to-one correspondence. [ABSTRACT FROM AUTHOR]

The periodicities of the climate change have long been explored by researchers not only because they reflect the inherent characteristics of the climate systems, but also because they are the foundations of climate-change predictability. This paper reports the periodicities of the hydroclimate variations reconstructed from a lacustrine sequence at Tiancun section (TC section) in the Luoyang Basin within the Central Plains of China and the sequence covers the first half of the Holocene. Our reconstruction shows that the hydroclimate variations at the TC section during the period from ∼10,135 and ∼ 5890 cal. yr BP were well corresponding with the effective soil moisture variations recorded by the stalagmite δ13C sequence at the Magou Cave. This corresponding relationship suggests that when the effective soil moisture increases (i.e., more negative δ13C values), the ratio of evaporation over precipitation in the paleolake at the TC section decreased, resulting in lower CaCO 3 content. It also suggests that when the effective soil moisture increases, more inflowing water entered the paleolake, resulting in coarser sediments. Our reconstruction also shows that the hydroclimate variations or lake level variations in the Luoyang Basin were characterized by millennial-scale quasi-periodicities that were most likely paced by the changes in ITCZ (Inter-tropical Convergent Zone) position and also by alterations in ENSO-like phase. And, both (ITCZ and ENSO) were most likely regulated by the solar activity. Our further analysis shows that the hydroclimate in the Luoyang Basin also experienced centennial-scale variations. Specifically, the grain size data express the following cycles: 692-year, 538-year, 217-year, 170-year and 123-year, all at the 99% confidence level. And, the CaCO 3 content data express the following cycles: 202-year, 184-year, 169-year and 85-year, all at the 99% confidence level. These cycles are approximately coincident with the widely-reported solar-activity cycles. • This paper reports the periodicities of the hydroclimate variations reconstructed from a lacustrine sequence in the Central Plains of China and the sequence covers the first half of the Holocene. • The hydroclimate variations were primarily paced by changes in ITCZ position and also by alterations in ENSO-like phase. And, both (ITCZ and ENSO) were most likely regulated by solar activity. • The centennial-scale hydroclimate variations were approximately coincident with the widely-reported solar-activity cycles. [ABSTRACT FROM AUTHOR]

Focusing on the evolution of coral reefs in the South China Sea, this special issue is dedicated to enhancing our understanding of Holocene environmental and climate changes in the region and their driving mechanisms. It comprises twenty-four papers organised into seven themes: (1) Palaeoclimate and palaeoenvironment evolution recorded by coral reefs; (2) Palaeo-ENSO activity recorded by coral reefs; (3) Palaeo-storm activity recorded by coral reefs; (4) The formation and evolution of coral reefs; (5) Carbonate diagenesis in coral reefs; (6) The application of new geochemical record indicators to coral reefs; and (7) Lipid biomarker records in coral reefs. This special issue provides an improved understanding of Holocene paleoclimates and paleoenvironments within the South China Sea, and the development of its coral reefs. It is hoped that these findings will deepen our knowledge of the natural and anthropogenic processes that contribute to climate and environmental change in the region, and aid the long-term protection of coral reef systems. • This special issue on recent advances of coral reefs in the South China Sea comprises twenty-four papers. • This special issue focuses on the evolution of coral reefs and their records on paleoenvironmental and paleoclimate changes. [ABSTRACT FROM AUTHOR]

For decades, it has been unclear as to how the world's first cities, in southern Mesopotamia, not only arose in a fluvial environment but also how this environment changed. This paper seeks to understand the long-term fluvial history of the region around Uruk, a major early city, in relation to water-human interactions. This paper applies geomorphological, historical and archaeological approaches and reveals that the Uruk region in southern Mesopotamia had been under the influence of freshwater fluvial environment since the early Holocene. It further demonstrates how canals and long-term human activities since the mid Holocene have been superimposed on the natural river channel patterns. Fieldwork has been conducted to ground-truth features identified applying remote sensing techniques. Five sediment cores were analysed to elucidate palaeoenvironmental changes. Radiocarbon ages for organic samples suggest that the oldest sediment layers, at a depth of 12.5 m, are from the Early Holocene, while results from diatom analyses imply that the whole sediment column was deposited in a freshwater environment. Intensive networks of palaeochannels and archaeological sites within the study area have been reconstructed and these networks have been divided into four different time intervals based on changes in channel courses. The first is from the early 4th to the late 1st millennium BCE; the second is from the late 1st millennium BCE to the middle 2nd millennium CE; the third lasted from after the Islamic period until the 1980s; the fourth is from the 1980s until the present. Key results include evidence for freshwater environments and favourable settlement conditions had already formed by the 8th millennium BCE. The favourable settlement environment resulted in stable (long-lived) canals between the 4th millennium BCE and 1st millennium CE. A significant settlement and irrigation expansion occurred in the early 1st millennium CE. Major abandonment ensued in the late 1st millennium CE and lasted until the mid 2nd millennium CE. [ABSTRACT FROM AUTHOR]

In a first paper, we presented an in-depth discussion and a computational method (free of the calendar problem) to reckon any kind of latitudinal insolation gradients, LIGs, throughout the Holocene and up to CE 3000. One of the main insights from this exact definition of LIGs is that, unlike what is argued in prior works, during the Holocene, a general classification of LIGs in terms of obliquity signal or climatic precession variations is much more complex, even in summertime. It is especially evident in the Southern Hemisphere, where summer half-year LIGs evolve under the relatively stronger modulation by climatic precession. In this work, the short-term periodicities (high frequency variations in time domain) of all these LIGs are studied by means of the multitaper spectral analysis. The goal is to get more insights on the competing effects between obliquity and climatic precession during the Holocene, and to know how the relative intensity of the obliquity's periodicities is when compared to the main spectral peaks produced by the climatic precession effects at short time scales (e.g., from annual to decadal bands). Our main result is the clarification of the role of the 18.63 yr periodicity originated in the well known retrograding cycle of the Moons' orbit. We found that this lunar cycle is always present at a 99 % significance level in all the analysed LIGs, even in winter with solar cycle included. The conceptual explanation of this persistence is based on the fact that all accurate short-term orbital forcing calculation must include the lunar nodal cycle even in climatic precession variations. We propose to use more specific definitions when short-term orbital variations are taken into account in describing Milanković forcing. [ABSTRACT FROM AUTHOR]

Most parts of the Circumpolar Arctic have only discontinuous evidence for long-term human settlement. In contrast, Northern Norway has an unbroken archaeological record that extends back to the early Holocene. Numerous high-resolution archaeological and palaeoenvironmental records have been generated by commercial excavations and surveys, offering archaeologists unique opportunities to investigate long-term human ecodynamics in an Arctic coastal setting. To date, however, deeper analysis of the new datasets has yet to be undertaken. This paper aims to present a new synthesis of early and mid Holocene archaeological and paleoenvironmental sequences for Western Finnmark (11500-2000 cal BP). This enables us to identify three major phases of culture change that broadly correlate with climatic and environmental shifts. We then present emerging results from our multi-scalar analysis of the processes driving these transformations. At supra-regional and regional scales, our palaeodemographic modelling indicates major population events centered around 6000 cal BP and 4000 cal BP. At intra-regional scales, we are identifying spatial clustering of prehistoric settlements into local socio-economic communities. At the scale of local settlements, our analysis of house-pit chronologies is clarifying the degree of simultaneous occupation and re-use. We also draw on recent research into rock art and ritual landscapes in an effort to reconstruct the relationship between settlement clusters and general interaction patterns. Integration of these diverse lines of evidence is generating a vivid picture of thriving Arctic coastal communities, with indications that the timing and pace of cultural responses to climatic and environmental changes were more complex than previously thought. [ABSTRACT FROM AUTHOR]

Palaeoclimatic records from southern tip of South America during the Last Holocene, indicate important climate intervals, such as the Medieval Climate Anomaly and Little Ice Age, which offered new scenarios to hunter-gatherer groups who inhabited the region. The aim of this paper is to explore the social practices carried out by hunter-fisher-gatherer societies of the southern part of the Atlantic Coast of Tierra del Fuego island (53–55°S, 66–74°W) in order to deal with these environmental changes. From our perspective, foragers have played an active role in designing strategies to cope with environmental fluctuations. Consequently, we argue that in a context of ecological uncertainty, these societies would have developed flexible strategies in terms of subsistence, technology and settlement patterns. In order to test this proposal, zooarchaeological and technological analysis of different archaeological assemblages dated between the 1300 to 220 BP were undertaken. The results show that these hunter-fisher-gatherer societies exploited a broad range of faunal resources using a versatile technology which encompassed tools with low production values and high use values. Likewise, the analysis of landscape organization revealed a settlement strategy centered on the most productive habitats, which were preferentially reoccupied. We suggest that these strategies, supported by cumulative knowledge and material conditions, could have enhanced social resilience and sustainability. [ABSTRACT FROM AUTHOR]

High-latitude permafrost peatlands are sensitive to global warming, and understanding their paleohydrological evolution is critical for assessing future hydrological and environmental changes. This paper presents a diatom record from a peat deposit covering the past 3300 years to reconstruct the moisture and acidity conditions in the Tuqiang permafrost peatland in the northern Greater Khingan Mountains of northeast China. Our findings are integrated with previously published records of plant macrofossils, palynology, and geochemistry from the same profile. From 3300 to 2800 cal yr BP, planktonic and benthic diatoms were equally abundant, indicating relatively high moisture conditions, while the low abundance of acidophilous diatoms reflects relatively high pH during this interval. Pollen data show dominance by sedges with input from the surrounding Pinus forest, while LOI data and lithology suggest that the site was a non-peat accumulating wetland. During the period 2800–1100 cal yr BP, the dominance of planktonic diatoms indicates a wetter local environment, concurrent with the dominance of peat-forming sedges (Eriophorum), indicating the development of a peatland. Between 1100 and 500 cal yr BP, a short-lived increase in acidophilous diatoms (Eunotia) marks a decrease in pH. Since 500 cal yr BP, the dominance of benthic diatoms reflects a drier environment, while a vegetation shift from an Eriophorum -dominated rich fen to a Sphagnum- and Ericaceae-dominated poor fen. An increase in Eunotia diatoms prior to the Sphagnum peak may indicate that diatoms are more sensitive to local acidified habitats than moss. Peatland development in the northern Greater Khingan Mountains was likely induced by the onset of a cooler and wetter climate starting at approximately 2800 cal yr BP, a scenario supported by regional paleoclimate records. Since 700 cal yr BP, the peatland has been affected by both anthropogenic activities and climatic changes, as a drying climate and intensified human activities around the study area reduced diatom species diversity and peat accumulation. Under the background of future global warming and enhanced human activities, the decreasing species diversity and carbon accumulation rate of peatlands in high-latitude permafrost regions need more attention. • Diatoms can indicate local moisture and acidity in permafrost peatlands. • Diatoms are likely more sensitive to microhabitats than bryophytes. • TQ peatland formed after 2800 cal yr BP caused by the cooler and wetter climate. • Rich-fen shifted to poor-fen which co-influenced by deforestation and dry climate at LIA. [ABSTRACT FROM AUTHOR]

Abstract The Maloti-Drakensberg Mountains are southern Africa's highest and lie at a crucial interface between the sub-continent's drier, colder, more seasonal interior and its perennially productive sub-tropical coastal belt. Their location, high elevation, and topography make them ideal for exploring human responses to late Quaternary climatic change. This paper reviews and synthesizes palaeoclimatic and palaeoenvironmental data from the Maloti-Drakensberg region over the past 50,000 years. It then employs 325 calibrated radiocarbon dates to examine human occupational trends across the region and its component parts, discuss human-environment dynamics over this time-span, and explore patterning between particular phases of climatic change and the timing, mode, and motives of its exploitation by people. Key findings are that the region's Lesotho core may have served as a refugium for human populations during drier, more unstable climatic periods and that intensified exploitation of freshwater fish likely helped address resource stress in cooler ones. An agenda for future palaeoenvironmental and archaeological research is also mapped out. Highlights • Elevation and location make the Maloti-Drakensberg highly sensitive to climate change. • Proxy data document greater moisture availability during glacial and stadial maxima. • Diverse climatic conditions saw pulsed human occupation of different sub-regions. • Mountain core provided refuge for human populations during drier/unstable episodes. • Flexible responses to resource stress included intensified fishing in cooler periods. [ABSTRACT FROM AUTHOR]

Differences between climate conditions during the Last Glacial Maximum (LGM) and the Mid-Holocene (MH) in southern South America inferred from the state-of-the-art PMIP3 paleoclimatic simulations are described for the first time in this paper. The aim is to expose characteristics of past climate changes occurred without human influence. In this context, numerical simulations are an indispensable tool for inferring changes in near-surface air temperature and precipitation in regions where proxy information is scarce or absent. The analyzed PMIP3 models describe MH temperatures significantly warmer than those of LGM with magnitudes of change depending on the season and the specific geographic region. In addition, models indicate that seasonal mean precipitation during MH increased with respect to LGM values in wide southern continental areas to the east of the Andes Cordillera whereas seasonal precipitation developed in areas to the west of Patagonian Andes reduced from LGM to MH. [ABSTRACT FROM AUTHOR]

Recent meta-analyses of Upper Paleolithic Southwestern European archaeofaunas (Jones, 2015, 2016) have identified a consistent “Mediterranean” cluster from the Last Glacial Maximum through the early Holocene, suggesting similarities in environment and/or consistency in hunting strategy across this region through time despite radical changes in climate. However, while these archaeofaunas from this cluster all derive from sites located within today's Mediterranean bioclimatic region, many of them are from locations far from the Mediterranean Sea – Atlantic Portugal, the Spanish Meseta – which today differ significantly from each other in biotic composition. In this paper, I explore clustering (through cluster analysis and non-metric multidimensional scaling) within the Mediterranean archaeofaunal group. I test for the influence of sample size as well as the geographic variables of site elevation, latitude, and longitude on variability in the large mammal portions of archaeofaunal assemblages. ANOVA shows no relationship between cluster-defined groups and site elevation or longitude; instead, site latitude appears to be a primary contributor to patterning. However, the overall compositional similarity of the Mediterranean archaeofaunas in this dataset suggests more consistency than variability in Upper Paleolithic hunting strategy in this region. [ABSTRACT FROM AUTHOR]

China is the country with the most population in the world, and its climate is extremely diverse due to tremendous differences in latitude, longitude, and altitude, ranging from tropical in the far south to subarctic in the far north and alpine in the higher elevations of the Qinghai-Tibetan Plateau. Accurate assessment of its modern climate change is conductive to addressing global warming threat. Along with the development of Past Global Changes (PAGES) research, the focus has changed from paleo-climate reconstructions to using paleo-data for assessing the present and predicting the future. Previous studies have been devoted to climate change assessment using modern climate observations and simulations. This paper presents a new assessment approach based on the mid-Holocene, which provides a naturally oriented warming that can be compared to modern human-made global warming. A variety of climatic data, including modern observations, paleo-climate records, CMIP5 (Coupled Model Intercomparison Project Phase 5) and PMIP3 (Paleoclimate Modelling Intercomparison Project 3) simulations, as well as lake level models, were applied in this synthesis. Numerical climate classification was introduced to evaluate climate change impacts to Chinese climate zones on various time scales. The results show that winter and summer seasons have different response to the naturally oriented mid-Holocene warming but human-made global warming makes the warming trend appear in all seasons. Temperate and continental dry winter climates expand dramatically during the mid-Holocene warm period; however, the future global warming could have few impacts to Chinese climate zones. Furthermore, the East Asian summer monsoon was strengthened obviously by the mid-Holocene warm climate and strong low-latitude insolation. There is no consistent trend both for the winter and summer monsoon on the background of human-made global warming. In this study, a new benchmark was established based on paleo-climate to evaluate the impacts of human-made global warming. [ABSTRACT FROM AUTHOR]

The 8.2 ka BP event may represent the largest, most abrupt Holocene climate event. This paper examines the impact of this event on human activity in the middle Mesolithic. It produces Bayesian statistical models for the chronology of anthropogenic sites in northwest Atlantic Europe for a 1000 year time window around the event to explore evidence for human responses to climate change or resilience in the face of this climate change event. By approaching evidence for activity at sites in Denmark, Belgium, France, Ireland and Britain we explore evidence for differential temporally- and spatially-transgressive local responses to climate change in this period to move to sub-continental scales of activity. [ABSTRACT FROM AUTHOR]

While mean grain size of sensitive component in muddy sediments from Chinese coastal seas was widely used as a proxy for reconstruction of the East Asian winter monsoon (EAWM) strength, many intractable problems still remain concerning the discrepancies in different studies. This paper provides a comprehensive overview of recent researches on the reconstruction of Holocene EAWM strength using sensitive grain size (SGS) in muddy sediments from the Chinese coastal seas. In the present study, 15 time-series of SGS in sediments from six mud areas are included. These records are summarized and compared during the last 8000 years, 3000 years and 150 years, respectively. The results show that trends of SGS time-series are inconsistent at millennial, multi-centennial and decadal time scales. The inconsistencies could be partly caused by age uncertainties and chosen SGSs. More important, grain size characteristics in sediments from some mud areas could be influenced by factors other than coastal currents driven by EAWM, such as sedimentary environments, riverine runoff and storms. Thus SGS of muddy sediments should be used with caution when reconstructing winter monsoon strength, especially those in the northern Yellow Sea and near the Yangtze River estuary. [ABSTRACT FROM AUTHOR]

This paper uses China's historical records to gather information on maritime disasters caused by tropical cyclones. Official records show that there were a total of thirteen major maritime disasters possibly caused by tropical cyclones. Maritime disaster variation trends indicate that tropical cyclones tend to strike the southern coast of China during a La Niña-like stage whereas an El Niño-like stage leads to tropical cyclones being guided northward toward the Korean Peninsula and Japan. During China's Yuan Dynasty (AD 1271–1368) Kublai Khan tried to invade Japan twice during an El Niño-like stage and encountered intense tropical cyclones, which the Japanese called Kamikaze . During a La Niña-like stage, multiple maritime disasters occurred in the East China Sea, the Taiwan Strait and the South China Sea in the Qing Dynasty (AD 1636–1912). Indeed, the historical record of the Qing Dynasty details maritime disasters at least 9 times. These events were also caused by tropical cyclones. In addition, statistics on the seasons of tropical cyclone genesis and their landfall locations from AD 1945–2013 in the Northwest Pacific Ocean region reveal that in summer, tropical cyclones tend to make landfall along coastal regions north of Fujian Province, eastern China; however, in autumn and winter, cyclones tend to be guided further southward to make landfall in southern China (Hainan), Vietnam, and the Philippines. This phenomenon in seasonal variation is reflected in the maritime disaster events recorded for coastal regions of southeastern China and landfall locations of tropical cyclones during the Qing Dynasty. [ABSTRACT FROM AUTHOR]

During the late Pleistocene and early Holocene, climatic, faunistic, and ecological changes could produce social readjustments and technological innovations in human populations that were exploring and colonizing the low southeastern plains of South America. In this paper, paleoecological and archaeological data are integrated to systematize and discuss different aspects of early human settlement in Uruguay and the south of Brazil. It is possible to recognize evidence of initial human dispersion by the region between ~14,000 and 13,100 cal BP (12,000 to 11,320 14C BP) during the late Pleistocene, when dry and cold climatic conditions prevailed in the region. Later, between 12,800 and 10,065 cal BP, a low plains Paleoamerican stemmed bifacial tradition emerged with three different techno-complexes, represented by Fishtail, Tigre, and Pay Paso projectile points. These groups were adapted to the grassland plains and characterized by the presence of wide-stemmed projectile points. The Fishtail point had been supplanted by the Tigre point, showing diversification in design of projectile points during the Pleistocene-Holocene transition. Approximately 12,000 to 11,200 cal BP in the middle Uruguay River, a social and technological reorganization occurred, along with the emergence of the Tigre techno-complex during post-Fishtail times. The advent of Tigre groups coincided with warmer and wetter climatic conditions, indicating the beginning of the Holocene. By 11,080-10,928 cal BP, new weaponry changes occurred in the region, including the production of the Pay Paso points, a regionally distinctive projectile-point style for the early Holocene. These aspects allow start discussions of cultural transmission, technological innovations and morphological variation in projectile point styles over the time and space. The field research developed over the past 15 years, in conjunction with the previous research conducted in southern Brazil, the relative high density of early sites with radiocarbon ages (n = 22), and the chronological base (67 radiocarbon ages), allow to formulate an archaeological and behavioral model about the initial peopling of the Uruguayan and southern Brazil plains. [ABSTRACT FROM AUTHOR]

Reconstructing Holocene changes in regional sea level is useful for understanding future sea-level scenarios. In this paper we examined the sedimentology, pollen, foraminifera, and organic matter properties of a well-dated profile from the Subei Basin that spans the last 6.7 ka. By integrating our findings with the archaeological record, we investigated mid- to late Holocene vegetation responses to relative sea-level fluctuations and considered the impact of climatic variations on cultural development. In the middle Holocene, the rapid and abrupt expansion of salt marsh vegetation (Chenopodiaceae, Cyperaceae, and Poaceae) suggests a relative rise in sea level. From 5.7 to 4.2 cal ka BP, lowland swamps were settled by Neolithic communities, as indicated by peak levels of microscopic charcoal and a significant rise in herbaceous pollen species, such as Cyperaceae, Typha , Myriophyllum , and Poaceae. From 4.2 to 3.7 cal ka BP, a major increase in Chenopodiaceae abundance and a δ13C excursion were observed along with a decrease in Cyperaceae and Poaceae levels, which revealed that human activity significantly decreased following the 4.2 ka climate event. Evidence suggests that the area under investigation experienced a relatively high sea level between 6.7 and 6.0 ka, a relative decrease in sea level between 6.0 and 5.7 ka, a steady sea-level condition between 5.7 and 4.2 ka, and gradual replacement by a freshwater marsh between 5.7 and 4.2 ka. The pollen and δ13 C records demonstrate that the relative sea level rose quickly from 4.2 to 3.7 ka, which could correspond to the 4.2 ka event. Enhanced El Niño-Southern Oscillation (ENSO) variance and intense climatic events in eastern China were the driving forces behind the mid-late Holocene relative sea-level shift. The rise in relative sea level eventually led to the collapse of the Qingdun and Jiangzhuang sites in the Subei Basin. Our results provide independent vegetation evidence of the simultaneous changes in relative sea level and variations in climate. • Vegatation and environment changes are investigated from ∼6700 cal a BP. • The significant relative sea-level rise in the Subei Plain during 4.2–3.7 cal ka BP. • The rise in relative sea level led to the collapse of the Qingdun site and Jiangzhuang site in the Subei Basin. [ABSTRACT FROM AUTHOR]

This paper presents and discusses the influence of climatic and edaphic factors on vegetation succession of the postglacial Lake Czarne (LC) located in NE Poland. On the basis of pollen, macroscopic plant remains, non-pollen palynomorphs (NPPs), and geochemical analyses, we reconstructed the transition from a clear oligotrophic lake to an ombrotrophic mire from 13,300 to 5900 cal. BP. Climatic events/periods that may have affected the lake/mire succession were as follows: (i) relatively warm conditions in the younger part of the Younger Dryas (ca. 12,220 cal. BP) that led to water eutrophication recorded as blooms of Scenedesmus ellipticus , whose response preceded that of woodland vegetation by ca. 200 years, (ii) the warming of the Late Glacial–Holocene transition and early Holocene that caused the final melting of dead ice block(s) and led to the deepening of the water body and/or an increase in the water level, the retreat of submerged macrophytes, and the enrichment of waters with sulphur, (iii) the global cold period between 8600 and 8000 cal. BP that contributed to a rise in the water level during the phase of sedge swamp and enabled the reappearance of Nymphaeaceae and blooms of S. ellipticus (ca. 8570–8500 cal. BP), and (iv) the global climate cooling 6500–5900 cal. BP that still remains enigmatic in terms of palaeobotanical patterns; however, geochemical markers point to an increase in the water level and enhanced erosion in the LC catchment ca. 6200–6000 cal. BP. Lake terrestrialization resulted in the concurrent appearance of microhabitats suitable for mosses with contrasting ecological preferences, e.g., Warnstorfia exannulata (acidic) and Scorpidium revolvens (alkaline), or Straminergon stramineum (acidic), Meesia triquetra (alkaline) and S. revolvens (alkaline). [ABSTRACT FROM AUTHOR]

The paper comprises data from 27 case studies to assess large-scale human-vegetation interferences in the Carpathian region during the Mid-Holocene. The main focus is put on herding-related vegetation changes and climate influences are addressed. The publications reviewed are based on sediment sequences which provide C 14 -dated pollen records, charcoal and geochemical data. Based on a semi-quantitative approach pollen of secondary indicator species and arboreal pollen values were combined in a fuzzy model to assess the intensity of herding-related vegetation changes. The model was applied for 20 selected case studies. The data from the remaining seven sites as well as geochemical and charcoal data were used to validate the results of the standardized evaluation. Speleothem δ 18 O and δ 13 C records from Hungary and Romania were used as independent proxies to align Holocene climate development. The results were regionalized and trends of herding-related vegetation change are presented for the Southern Carpathians and Apuseni Mountains, for the Eastern Carpathians and for Hungary. Mean distances between included archives and prehistoric settlement sites were calculated as indicator for the marginality of the environmental archives. In all regions, absolute values for herding indication are low. Phases of changing herding impact on the landscape can be observed for the Southern Carpathians and Apuseni Mountains as well as for Hungary. In the Southern Carpathians and Apuseni Mountains increased herding activities can be traced for the Early Chalcolithic and the Late Bronze Age. The first phase is contemporary with an intensification of the use of secondary products. In Hungary herding impact is in accordance with prehistoric settlement development. Widely increased herding indications date to the Late Chalcolithic and the Early Bronze Age. In the Eastern Carpathians, interference of climate influences and human impacts occurred. [ABSTRACT FROM AUTHOR]

This synthesis paper summarizes published proxy climate evidence showing the spatial and temporal pattern of climate change through the Holocene in Arctic Canada and Greenland. Our synthesis includes 47 records from a recently published database of highly resolved Holocene paleoclimate time series from the Arctic (Sundqvist et al., 2014). We analyze the temperature histories represented by the database and compare them with paleoclimate and environmental information from 54 additional published records, mostly from datasets that did not fit the selection criteria for the Arctic Holocene database. Combined, we review evidence from a variety of proxy archives including glaciers (ice cores and glacial geomorphology), lake sediments, peat sequences, and coastal and deep-marine sediments. The temperature-sensitive records indicate more consistent and earlier Holocene warmth in the north and east, and a more diffuse and later Holocene thermal maximum in the south and west. Principal components analysis reveals two dominant Holocene trends, one with early Holocene warmth followed by cooling in the middle Holocene, the other with a broader period of warmth in the middle Holocene followed by cooling in the late Holocene. The temperature decrease from the warmest to the coolest portions of the Holocene is 3.0 ± 1.0 °C on average (n = 11 sites). The Greenland Ice Sheet retracted to its minimum extent between 5 and 3 ka, consistent with many sites from around Greenland depicting a switch from warm to cool conditions around that time. The spatial pattern of temperature change through the Holocene was likely driven by the decrease in northern latitude summer insolation through the Holocene, the varied influence of waning ice sheets in the early Holocene, and the variable influx of Atlantic Water into the study region. [ABSTRACT FROM AUTHOR]

As a part of the INQUA project “A Global Digital Database and Atlas of Quaternary Dune Field and Sand Seas”, 337 age records from the desert dunes of China and 20 from Mongolian dune fields have been compiled in the database. This has opened the possibility of exploring and synthesizing the Quaternary environmental changes in the Asian mid-latitudes dune fields directly from the on-site aeolian sand archives. This paper assessed the sand dune chronologies in terms of geographical distribution, data quality and their implications for late Quaternary palaeoenvironmental reconstructions. The available ages are concentrated mainly in the last 20 ka and many are from the fields of stabilized dunes in the eastern portion of the desert belt in northern China. The number of records and the ratio between the records of stable state and the total records could act as a proxy for the palaeoenvironmental interpretation. The aeolian sand activities deciphered from the chronological data in the eastern portion of the desert belt in northern China show a reasonable correlation with the general global climatic curves at the glacial–interglacial timescales. The limited aeolian sand records from the glacial period, however, hamper the understanding of the detailed features (e.g., forms and processes) of the dune fields during glacial times. In the last two millennia, however, there has not been any meaningful correlation between aeolian dune activity and climatic variation at the centennial time scales, probably due to the complexity of the aeolian sand systems and human interventions. Extending the coverage of dune chronology both temporally and spatially is urgently needed for a full understanding of the environmental changes in the dune fields. [ABSTRACT FROM AUTHOR]

Climate change is often cited as a major factor in social change. The so-called 8.2 ka event was one of the most pronounced and abrupt Holocene cold and arid events. The 9.2 ka event was similar, albeit of a smaller magnitude. Both events affected the Northern Hemisphere climate and caused cooling and aridification in Southwest Asia. Yet, the impacts of the 8.2 and 9.2 ka events on early farming communities in this region are not well understood. Current hypotheses for an effect of the 8.2 ka event vary from large-scale site abandonment and migration (including the Neolithisation of Europe) to continuation of occupation and local adaptation, while impacts of the 9.2 ka have not previously been systematically studied. In this paper, we present a thorough assessment of available, quality-checked radiocarbon ( 14 C) dates for sites from Southwest Asia covering the time interval between 9500 and 7500 cal BP, which we interpret in combination with archaeological evidence. In this way, the synchronicity between changes observed in the archaeological record and the rapid climate events is tested. It is shown that there is no evidence for a simultaneous and widespread collapse, large-scale site abandonment, or migration at the time of the events. However, there are indications for local adaptation. We conclude that early farming communities were resilient to the abrupt, severe climate changes at 9250 and 8200 cal BP. [ABSTRACT FROM AUTHOR]

Turbidity current is one of the most important mechanisms for rapid transportation of terrigenous sediments from the continental margin to the deep sea. Although extensive work on turbidite systems has been carried out globally, the Tanzanian margin, off East Africa, is poorly understood. This paper will therefore use a well-dated high-resolution marine core (GeoB12624-1), obtained during RV Meteor Cruise M75/2, from the upper Tanzanian continental slope, offshore the Rufiji River delta, to demonstrate which environmental parameters, e.g., climate versus sea level, control the temporal distribution of the turbidite deposits during the last deglaciation and the Holocene. Results show that the turbidite deposits are composed of coarser-grained sediments with normally graded bedding. The thickness, mean grain size and frequency of the turbidite beds were estimated to detect turbidity current activity since the Last Glacial Maximum (LGM). A total of 12 turbidite beds (TI-T12) was recognized and divided into three intervals, based on the presence and intensity of the turbidite deposits. (I) a glacial sea-level lowstand (LGM and Heinrich Stadial 1; 19.3–14.6 ka): suppressed turbidity current activity due to arid conditions in the hinterland and sea-level lowstand. (II) A deglacial sea-level rise period (Bølling-Allerød interval to the early Holocene; 14.6–8 ka): turbidity current activity started to be strengthened during the Bølling-Allerød warming interval (T1), followed by a first increase in turbidite frequency, thickness and mean grain-size during the Younger Dryas (T2–T4) and a second increase during the early Holocene (T5–T10). (III) An interglacial sea-level highstand period (mid-to late Holocene; 8–2.5 ka): turbidity current activity diminished from the mid- (T11, T12) to late Holocene. This temporal distribution of turbidite deposits indicates that turbidity currents were most active during the last sea-level rise, synchronous with more humid climate in the hinterland, than during a sea-level lowstand (e.g., LGM) when climate was more arid. Thus, we propose that it is the climate conditions in the hinterland that form the primary controlling factor for turbidity current activity of Tanzanian slope. The remobilization of lowstand sediments on the Tanzanian continental margin during a sea-level rise, combined with shedding sediments towards the study area from the main canyon/channel, also plays a role in supplying new sediments to the turbidite system. These new data demonstrate that, in specific continental margin, high fluvial discharge will promote sediment transfer along the shelf and slope even during sea-level rise and highstand. [ABSTRACT FROM AUTHOR]

This paper presents the first high-resolution Holocene stalagmite record of Taiwan from Jianfei Cave (22°50.873 N; 120°21.255 E) in Dagangshan Mountain, South Taiwan. The 13.6-cm long stalagmite (DGS-1) has been dated by AMS 14 C dating, spanning from AD 700 to AD 1933. The δ 18 O, δ 13 C and XRF scanned elemental profiles reveal interannual variations in climate and environmental conditions, with light δ 18 O and δ 13 C excursions reflecting wet climate and better vegetation coverage under stronger East Asia Summer Monsoon (EASM). Dark layers in DGS-1 containing high Fe, Mn and Sr contents were formed during dry episodes. Five periods with different climate regimes and vegetation conditions can be identified in the DGS-1 record: Period I (AD 700–1200) and Period V (AD 1810–1933) had warm and wet climates with good vegetation coverage. A drying trend probably corresponding to the switch from El Niño-like to La Niña-like oceanic condition occurred during Period II (AD 1200–1400). Cold but relatively wet climates with good vegetation coverage were prevailed during Period III (AD 1400–1610), whereas cold and dry climates with poor vegetation coverage were dominated during Period IV (AD 1610–1810). Based on the rainfall record of Tainan since AD 1897 and the stalagmite record, we found that stronger total solar irradiation (TSI) resulting in strong EASM produces heavy rainfall in South Taiwan on interannual-to-decadal scales; and vice versa. The 117-yr instrumental rainfall record of Tainan showed that rainfall in Tainan decreased during April-to-June and strongly increased during July-to-September in many La Niña years (positive SOI and negative Niño 3.4). This may be because weaker Meiyu rainfall but stronger tropical Equatorial Pacific cyclones (or typhoon) under La Niña condition. Thus, it is better to use seasonal rainfall for detecting relationship between Tainan rainfall and ENSO. On decadal-to-centennial scales, strong El Niño-like state and warm Pacific Decadal Oscillation (PDO) phase are in favor of wet conditions in South Taiwan. [ABSTRACT FROM AUTHOR]

Studies dealing with the reconstruction of Holocene climate change of tropical areas are scarce. Of these, multi-proxy investigations using peatlands are still absent. In this paper, we present the Holocene record of environmental changes in central–eastern Brazil reconstructed from a core sampled in Pau de Fruta mire (Serra do Espinhaço Meridional, Brazil). We combined palynological and geochemical analyses, supported by core stratigraphy, 14 C dating and multivariate statistics. The location of the mire is ideal because it is in an area which is directly associated with the South Atlantic Convergence Zone (SACZ). Six main phases of change suggested by vegetation and local and regional landscape dynamics were described. In phase I (~ 10,000–7360 cal. yr BP) the climate was very wet and cold and was accompanied by soil instability in the mire catchment (severe local erosion) and the 8.2 ka event was easily recognizable by a large increase in the deposition of regional dust. Phase II (~ 7360–4200 cal. yr BP) was characterized by wet and warm conditions, catchment soil stability and enhanced deposition of regional dust. In phase III (~ 4200–2200 cal. yr BP), climate was dry and warm and soil erosion in the catchment increased again. In phase IV (~ 2200–1160 cal. yr BP) dry and punctuated cooling was reconstructed, together with enhanced deposition of regional dust. Phase V (~ 1160–400 cal. yr BP) reflects sub-humid climatic conditions (like the current climate), the lowest inputs of local and regional dust and the largest accumulation of peat in the mire. While in phase VI (< ~ 400 cal. yr BP) sub-humid conditions continued but both local and regional erosion significantly increased. Our results demonstrate that the tropical peatlands of Serra do Espinhaço Meridional contain relevant records of Holocene climate changes, and that a multi-proxy approach offers good opportunities for a detailed reconstruction of palaeoenvironments. [ABSTRACT FROM AUTHOR]

When dealing with current and past landscape evolution, a key issue addresses responses of geomorphic systems to the large number of influencing variables. Identifying morphodynamic phases and revealing interrelations with specific driving forces are demanding tasks for Quaternary research. In this paper, we present late Pleistocene and Holocene fluvial sedimentation patterns of three Western Mediterranean river catchments, namely Jarama River, Guadalete River and Guadalquivir River that extent along a climatic transect from semi-humid SW-Spain to semi-arid central Spain. These studies are based on extensive fieldwork conducted on 36 exposures and 13 drillings in floodplain positions. Field data is supported by geochemical analyses, while the chronological framework was obtained from the analyses of 70 radiocarbon samples. Results show distinct patterns of fluvial sedimentation as well as soil formation linked to floodplain stability for each river catchment. On regional or catchment scale, pollen stratigraphical correlation and comparison with lacustrine records show that fluvial dynamics have a strong reaction to climatic shifts, with phases of high fragility characterized by catchment erosion and floodplain sedimentation in response to climatic aridification events and phases of climate change in general. The comparison of the examined river systems reveals that periods of supra-regional floodplain sedimentation in several catchments occurred from 8.0 to 7.0, 5.0 to 3.8, 2.2 to 1.5, and around 1.0 as well as 0.4 ka cal. BP, while we found periods of supra-regional soil formation from 13.3 to 12.7, 7.0 to 5.1 (with a short interruption around 6.0 to 5.5 ka), 2.8 to 2.3 ka, 1.4 to 1.2 ka, and 0.8 to 0.5 ka cal. BP. Beside these consistencies we found deviating dynamic patterns that are apparently expressed in terms of differing onset and offset, differing durations, or even the lack of fluvial system response. The main reasons for this can be seen in different regional climate condition and impacts of further influencing factors, or in different levels of sensitivity of the river catchments that may be controlled by initial hydrological conditions, catchment size, or the degree of anthropogenic influence. A larger scale assessment shows that fluvial dynamic patterns are hardly comparable across entire Spain due to strong spatial heterogeneity of physiographic and climatic conditions on the Iberian Peninsula, in particular when areas are influenced by different circulation systems (e.g. regions influenced by the Atlantic Ocean vs. regions influenced by the Mediterranean Sea). However, the consideration of North Atlantic marine records reveals a certain coupling between North Atlantic coolings, atmospheric processes leading to arid climate over large parts of Spain, as well as increased landscape instability including strong fluvial sedimentation activity. Attendant atmospheric conditions are discussed. [ABSTRACT FROM AUTHOR]

Cova Colomera is one of the most important archaeological sites to explain early herding activities in the Central Pre-Pyrenees (Iberian Peninsula). Fieldworks have provided a stratigraphy that shows short occupations of the cave by Neolithic and Bronze Age human groups. The sedimentological description has revealed fumiers deposits, that are characteristic of husbandry activities. In this paper, we provide the anthracological results based on 1117 charcoal fragments. The results allow to characterise the Mediterranean vegetation landscape and its transformation, from a local perspective, related to climatic changes and anthropogenic activities. Climate changes and human activities have played a significant role in Mediterranean landscapes dynamics. However, the incidence or impact of both agents on the vegetation landscape occurred unequally among the Mediterranean region. The anthracological results from Cova Colomera suggest that the Central Pre-Pyrenees was dominated by an oak forest ecosystem, with sub- and supra-Mediterranean deciduous taxon and coniferous forest during the Middle Holocene. This ecosystem remained more or less stable during the Late Holocene, although evergreen oak showed a slight increase, and coniferous forest showed a slight decrease. The orographic characteristics of the Central Pre-Pyrenees were able to maintain temperate and humid conditions, with less impact of aridity events recorded in Mediterranean environments. From a diachronic point of view, the herding activities of Neolithic human and Bronze Age human groups do not appear to have affected highly the landscape development of the Central Pre-Pyrenees. Human activities were probably not intensive in terms of forest clearing or land use. • Middle-Late Holocene anthracological sequence of Cova Colomera. • Anthracological data shows local woodland peculiarities and changes. • Local humid conditions would have been favourable for meso-thermophilic taxa. • The earliest evidence of herding activities in the Central Pre-Pyrenees. • Human activities would have had less impact on the local forest's development. [ABSTRACT FROM AUTHOR]

Mediterranean fluvial hydrology is characterised by decadal-to-multi-centennial length wet and dry episodes with abrupt transitions related to changes in atmospheric circulation. Since the mid-1990s site-based flood chronologies from slackwater deposits in bedrock rivers and regionally aggregated flood histories from alluvial deposits have developed increasingly higher resolution chronological frameworks, although regional coverage is still uneven. This paper analyses the spatial and temporal distribution of extreme Holocene hydrological events recorded in fluvial stratigraphy in the Iberian Peninsula (Spain and Portugal), southern France, southern Italy, Northern Africa (Morocco and Tunisia) and eastern Mediterranean (Greece, Crete, Turkey, Cyprus and Israel). This study constitutes the most comprehensive investigation of Holocene river flooding ever undertaken in the Mediterranean and is based on the analysis of 515 14 C and 53 OSL dates. It reveals that flood periods in different regions cluster into distinct time intervals, although region-wide flooding episodes can be identified at 7400–7150, 4800–4600, 4100–3700, 3300–3200, 2850–2750, 2300–2100, 1700–1600, 1500–1400, 950–800, ca. 300, 200–100 cal. BP. Periods with more frequent floods in the western Iberian region coincide with transitions to cool and wetter conditions and persistent negative NAO mode. In Northern Africa increased flood frequency coincides with periods of generally drier climate, while in the eastern Mediterranean there is a higher incidence of extreme flood events under wetter conditions. Our meta-data analysis identifies an out-of-phase pattern of extreme events across the Mediterranean over multi-centennial timescales, which is particularly evident between the western Iberian and eastern Mediterranean regions. This centennial-to-multi-centennial see-saw pattern in flooding indicates that bipolar hydroclimatic conditions existed in the Mediterranean during the Holocene. [ABSTRACT FROM AUTHOR]

It is widely accepted that climate has a strong impact and exerts important feedbacks on erosional processes and sediment transport mechanisms. However, the extent at which climate influences erosion is still a matter of debate. In this paper we test whether frost-cracking processes and related temperature variations can influence the sediment production and surface erosion in a small catchment situated in the eastern Italian Alps. To this extent, we first present a geomorphic map of the region that we complement with published 10 Be-based denudation rates. We then apply a preexisting heat-flow model in order to analyze the variations of the frost-cracking intensity (FCI) in the study area, which could have controlled the sediment production in the basin. Finally, we compare the model results with the pattern of denudation rates and Quaternary deposits in the geomorphic map. The model results, combined with field observations, mapping, and quantitative geomorphic analyses, reveal that frost-cracking processes have had a primary role in the production of sediment where the intensity of sediment supply has been dictated and limited by the combined effect of temperature variations and conditions of bedrock preservation. These results highlight the importance of a yet poorly understood process for the production of sediment in mountain areas. [ABSTRACT FROM AUTHOR]

The Levant, a transition zone between the temperate Mediterranean domain and subtropical deserts, is a key area to study the latitudinal migrations of zonal climatic belts in response to glacial-interglacial conditions. The region underwent large climatic shifts during the Late Quaternary, with dramatic impacts on water resources and human populations. This paper presents the unique long-term hydroclimatic record (ca. 400 ka) from Northern Levant, derived from a sediment core taken from a small tectonic basin of northern Lebanon, the currently wettest area of the Levant. Combined biotic (pollen, biologic aquatic remains) and abiotic proxies (sediment properties, carbonate oxygen isotopes) reveal relatively high water availability during interglacials and generally drier glacials periods during the past four climate cycles. These general trends are in line with pollen records from southeastern and near east Mediterranean areas, but differ from some paleohydrological records from the southern Levant. Southward migrations of the rain-bearing mid-latitude westerlies during glacial periods and regional land topography are likely to explain the observed regional climate signatures. In addition, distinctive climate signatures of the successive wetter/drier intervals reflect interactions between global forcing (insolation, atmospheric greenhouse gas concentration), eastern Mediterranean Sea surface conditions intimately linked to North Atlantic climate and to ice-sheet and sea-ice extent at high northern latitudes, land topography, and local hydrogeological processes. Our record brings new benchmarks for understanding the spatial heterogeneity of eastern Mediterranean responses to global climate changes. [ABSTRACT FROM AUTHOR]

This paper reviews the published literature regarding the climatic and hydrological variations of the past 8000 years in the northern Xinjiang of China in hope that some of the controversies surrounding the Holocene climate history can be reconciled. Based on the well-tested premise that the overall relationship between the A/C ratios and the bioclimates in arid and semi-arid areas of China still holds, we compared the A/C ratio-based SMI (Standardized Moisture Index) of five selected lacustrine sequences. Our comparison shows that the regional average SMI had a general rising trend, and the rising trend was reasonably corroborated by other pollen proxies. The rising trend can be explained by invoking its climatic linkage with the North Atlantic Ocean, and a possible linkage with ENSO is an additional or an alternative mechanism for explaining the rising trend. The nearly parallel rising trends of seven δ 18 O-indicated SSI curves (Standardized Salinity Index) mean that the lake-water salinity has been rising since ∼8.0 cal. ka BP. The rising trend can be explained by invoking the Holocene variations in the areal extent of ice covers in the Tianshan Mountains and the Altay Mountains. That is, the persistent shrinking of the ice extent in the mountains generated less and less melting water supplies to the lakes and thus resulted in saltier and saltier waters in the lakes. The contradiction between the increasing trend of the basin-wide moisture and the increasing trend of the lake-water salinity can be reconciled as follows: the increasing trend of the precipitation accompanied by the lowering tend of the temperature might have increasingly enhanced the effective soil moisture in northern Xinjiang, but the increase in the basin-wide moisture was not enough to compensate for the decrease in the lake inflowing water resulted from the shrinkage of ice-covered areas in the mountains. [ABSTRACT FROM AUTHOR]

South Africa's southwestern Cape occupies a critical transition zone between Southern Hemisphere temperate (winter) and tropical (summer) moisture-bearing systems. In the recent geological past, it has been proposed that the relative influence of these systems may have changed substantially, but little reliable evidence regarding regional hydroclimates and rainfall seasonality exists to refine or substantiate the understanding of long-term dynamics. In this paper we present a mid-to late Holocene multi-proxy record of environmental change from a rock hyrax midden from Katbakkies Pass, located along the modern boundary between the winter and summer rainfall zones. Derived from stable carbon and nitrogen isotopes, fossil pollen and microcharcoal, these data provide a high resolution record of changes in humidity, and insight into changes in rainfall seasonality. Whereas previous work concluded that the site had generally experienced only subtle environmental change during the Holocene, our records indicate that significant, abrupt changes have occurred in the region over the last 7000 years. Contrary to expectations based on the site's location, these data indicate that the primary determinant of changes in humidity is summer rather than winter rainfall variability, and its influence on drought season intensity and/or length. These findings are consistent with independent records of upwelling along the southern and western coasts, which indicate that periods of increased humidity are related to increased tropical easterly flow. This substantially refines our understanding of the nature of temperate and tropical circulation system dynamics in SW Africa, and how changes in their relative dominance have impacted regional environments during the Holocene. [ABSTRACT FROM AUTHOR]

The Taosi site (4300–4000 BP) in the southern Linfen basin of Shanxi province is regarded as one of the most important large settlement sites prior to the origin of Chinese civilization, but the environmental context of its formation remains unclear. In this paper, we reconstruct the Holocene environment, based on analyses of OSL dates, pollen, grain sizes, magnetic susceptibilities, and trace elements of the two loess-paleosol profiles in Linfen basin, and discuss its influence on Neolithic cultural evolution in the area, and the formation of the Taosi site. The results indicate that the climate was warm and wet ca. 9.0–4.9 ka, promoting the development of the Neolithic cultures during that period in the Linfen basin. Climate turned cool and dry after 4.9 ka, and settlements concentrated in the valleys of the large rivers resulting in greater culture development and increasing political centralization. The development of Neolithic cultures coupled with paleosol enriched in micronutrient elements in Linfen basin provided a cultural basis and material basis for the Taosi culture. The central geographic location of the Taosi culture amidst various other early Chinese cultures contributed to the flourishing of the culture and the formation of the Taosi site as a major protourban settlement that influenced further evolution of Chinese social systems. [ABSTRACT FROM AUTHOR]

This paper presents a new fossil pollen record from Tso Moriri (32°54′N, 78°19′E, 4512 m a.s.l.) and seeks to reconstruct changes in mean annual precipitation (MAP) during the last 12,000 years. This high-alpine lake occupies an area of 140 km 2 in a glacial-tectonic valley in the northwestern Himalaya. The region has a cold climate, with a MAP <300 mm, and open vegetation. The hydrology is controlled by the Indian Summer Monsoon (ISM), but winter westerly-associated precipitation also affects the regional water balance. Results indicate that precipitation levels varied significantly during the Holocene. After a rapid increase in MAP, a phase of maximum humidity was reached between ca. 11 and 9.6 cal ka BP, followed by a gradual decline in MAP. This trend parallels the reduction in the Northern Hemisphere summer insolation. Comparison of different palaeoclimate proxy records reveal evidence for a stronger Holocene decrease in precipitation in the northern versus the southern parts of the ISM domain. The long-term trend of ISM weakening is overlaid with several short periods of greater dryness, which are broadly synchronous with the North Atlantic cold spells, suggesting reduced amounts of westerly-associated winter precipitation. Compared to the mid and late Holocene, it appears that westerlies had a greater influence on the western parts of the ISM domain during the early Holocene. During this period, the westerly-associated summer precipitation belt was positioned at Mediterranean latitudes and amplified the ISM-derived precipitation. The Tso Moriri pollen record and moisture reconstructions also suggest that changes in climatic conditions affected the ancient Harappan Civilisation, which flourished in the greater Indus Valley from approximately 5.2 to 3 cal ka BP. The prolonged Holocene trend towards aridity, punctuated by an interval of increased dryness (between ca. 4.5 and 4.3 cal ka BP), may have pushed the Mature Harappan urban settlements (between ca. 4.5 and 3.9 cal ka BP) to develop more efficient agricultural practices to deal with the increasingly acute water shortages. The amplified aridity associated with North Atlantic cooling between ca. 4 and 3.6 and around 3.2 cal ka BP further hindered local agriculture, possibly causing the deurbanisation that occurred from ca. 3.9 cal ka BP and eventual collapse of the Harappan Civilisation between ca. 3.5 and 3 cal ka BP. [ABSTRACT FROM AUTHOR]

Lacustrine-peat sediments from the Oskino-09 borehole in Western Siberia, which span the last 7.5 cal ka BP, were sampled for pollen and plant macro-remains to better understand regional climatic changes and the position of the forest-steppe border. Analysis of palynological assemblages indicate that meadow-steppe landscapes occupied the largest area in the middle of the Holocene (7.5–4.7 cal ka BP) due to reduced effective moisture during a warm climate interval. A subsequent gradual decrease in temperatures and evaporation led to an increase in effective moisture and emergence of birch groves during 4.7–2.0 cal ka BP, with short interruptions at ca. 3.3 and 2.5 cal ka BP. The expansion of pine forests and the advance of taiga to the south were recorded at ca. 2.0 cal ka BP. There is little evidence for significant human impact on forest-steppe belt evolution, and specifically evidence for anthropogenic deforestation on the southern border of the taiga is lacking. Human activities did not start to impact forests until the emergence of semi-nomadic cattle breeding in the Iron Age. A methodological finding of this paper is that we show that the Landscape Reconstruction Algorithm (LRA) is not always reliable and often overestimates forested areas. • Forests area is overestimated by quantifying landscape assessment in forest-steppe. • Largest meadow-steppe areas were due to reduced effective moisture ca 7.5–4.7 ka BP. • Intensive spread of coniferous in Western Siberian forest-steppe ca 2.0 ka BP. • Human impact on the landscape of Western Siberian forest-steppe was not significant. [ABSTRACT FROM AUTHOR]

In tropical Africa, Late Pleistocene-Holocene climatic fluctuations heavily impacted the continental hydro-systems. The timing and magnitude of 'African Humid Period' hydrological dynamics (AHP; ~14.8 to ~5.5 ka BP) are not yet fully understood due to the extreme variability in African geomorphic patterns and the complex network of past air convergence boundary shifts. The investigation of the functioning of specific hydro-sedimentary basins is needed to improve our knowledge on the AHP spatial and chronological patterns over the continent. In this paper we present a revised Holocene lake level curve of Lake Abhe: an endorheic basin situated in the Afar Depression at the northern extremity of the East African Rift System (EARS). Located at the boundary of the Red Sea and the Indian and Atlantic Oceans' air moisture mass fluxes, the Lake Abhe watershed represents a system sensitive to changes in Northeast African hydro-climate. Based on numerous littoral lacustrine geomorphic features and 53 related radiocarbon ages on stromatolites and nearshore deposits, we have defined the main Holocene lake highstands proposing a detailed paleo-shoreline record. The first rise in water level is dated to ~11.1 ka cal. BP, while the Maximal Holocene Highstand Shoreline (~420 m a.s.l.) was rapidly reached around ~10 ka cal. BP. Evidence of the impact of the 8.2 ka North Atlantic cooling event is recognized with slow lake level regression until ~8.3 ka cal. BP and with an abrupt drop at ~8 ka cal. BP. The resurgence of humid conditions was recorded from ~7.7 ka cal. BP to ~4.6 ka cal. BP. Radiocarbon ages on littoral materials allow us to propose a Holocene subsidence rate of the Abhe basin axial valley. Furthermore, multiphase sill overflow incisions towards the downstream Hanle basin and transient fluvial connectivity with the upstream Ziway-Shala basin, indicate strong geomorphic controls on lake highstand elevations. In summary, Lake Abhe Holocene fluctuations are the result of combined hydro-climatic, tectonic and local geomorphic controls. However, the confrontation with others East African basins allows us to discuss the transport of moisture masses dynamics into the northern EARS during the Holocene. [ABSTRACT FROM AUTHOR]

Coastal morphodynamics and environmental changes have been obviously altered by global warming, sea-level fluctuations, and human activities. Palynological analysis is one of the most important tools for providing information on vegetation, climate, and environmental change, which can be relatively sensitive indicators of human activity during the Holocene. However, Holocene coastal morphodynamics and palynological evidence from the Pearl River Delta and coastal areas has not been sufficiently studied. In this paper, we carry out analyses using detailed grain-size and palynological records of pollen, spores, freshwater algae, and marine dinoflagellate cysts from Borehole QZK13 in the Pearl River Estuary (PRE), southern China. The results show information relating coastal morphodynamics, vegetation evolution, climate changes, and anthropogenic activities during the Holocene based on radiocarbon chronology. In general, the PRE experienced marine transgressive processes; sea-level and the coastline tended to migrate landward between 10,700 and 4250 cal yr BP. Meanwhile, abundant arboreal pollen (mainly Castanopsis , Quercus -evergreen, Oleaceae, and Castanea) and small amounts of non-arboreal pollen (mainly Poaceae, Cyperaceae, and Artemisia) were observed in Borehole QZK13, which suggests that subtropical evergreen broadleaved forests were distributed throughout the PRE and adjacent areas, and relatively warm and moist climatic conditions were present during the early-middle Holocene. After that, there were relatively cool and wet climatic conditions, and marine regressive processes occurred in the PRE during the Late Holocene (ca. 4250–960 cal yr BP) indicated by an abrupt increase in aquatic herbs and Dicranopteris. Moreover, we hypothesize that the Neolithic "cultural fault" in the PRE is likely related to frequent storm surges induced by extreme typhoon events that occurred ca. 3000–2700 yr BP. • Grain size, pollen, spores, freshwater algae and dinoflagellate cysts from the Pearl River Estuary were investigated. • Three major phases shown by palynological results were corresponding to the changes in vegetation and climate. • We hypothesized that the Neolithic "cultural fault" is probably related to the storm surges induced by extreme typhoon events. • Natural vegetation cover has suffered large-scale destruction by ancient humans during the Late Holocene. [ABSTRACT FROM AUTHOR]

The Bay of Brest (BB) is a mixed, tide-dominated estuarine system. The shore terraces of this bay are occupied by modern free-living (calcareous) coralline algae locally termed "maerl", organized in bed-like morphologies (rhodolith deposits). Cores retrieved from around the bay reveal fossilized primitive maerl beds of Holocene age, interbedded in sandy-silt sedimentation. The alternation between biogenic constructions and estuarine sedimentation may provide evidence of varying environmental conditions of the late-Holocene period. This paper mainly focuses on the results of chronostratigraphic and bio-sedimentological interpretations of coring data collected in less than 15 m of water depth in an attempt to decipher the main stages of maerl colonization in the bay. In particular, this study raises several significant points allowing to draw links between centennial to millennial-scale climatic changes in marine estuary sedimentation and episodes within the development of maerl biocenoses. The paleo-bathymetry of the coastal terraces has not changed significantly over the last 5000 years. Yet, the first maerl occurrence only appeared around 2000 cal yr B.P., likely showing that the environmental conditions were not favorable for their emergence prior to that time. Pioneer maerl beds developed on coarse shell deposits inherited from the paleostorms affecting the Atlantic coasts during the colder climatic period of the Iron Age (3100–1950 cal yr B.P.). The accumulations then aggraded at various and discontinuous rates, sometimes reaching up to 2.1 m/kyr. Maerl beds temporarily disappeared in the southern part of the Bay of Brest when sedimentation rates increased throughout the bay during the Dark-Age cold period (1375–1250 cal yr B.P.), suggesting that maerl formations could not keep up with sedimentation rate exceeded a certain threshold. Muddy sedimentation conditions also dramatically changed on two occasions, with the establishment of coarse storm levels, set at the intervals 825–600 cal yr B.P. (MWP) and 113–0 cal yr B.P. But maerl deposits reseed the environment as a result of each new cold period, demonstrating the persistence of such coralline algae against drastic palaeoenvironmental changes in coastal areas. • Stratigraphy of late-Holocene estuarine sediments reveals interbedded maerl beds. • First maerl occurrence in the Bay of Brest is dated around 2000 cal yr BP. • Development of maerl beds coincides with the onset of colder and drier climates. • Maerl building phases are disrupted by periods of climate deterioration. • Coarse sedimentary deposits are associated with increased paleostorm activity. [ABSTRACT FROM AUTHOR]

In the Central Atacama Desert (22°-24°S; henceforth CAD), around 3700 cal yrs BP, human economies begin to transition from relying mostly on hunting and gathering to increasingly incorporating horticulture and pastoralism became more intensive during the Late Intermediate Period (LIP; beginning at ca. 1050 cal yrs BP/900 AD). In this extreme environment, the well-being of past and present farming and herding communities is directly tied to water availability. The lack of proper paleoclimatic/environmental records in terms of their temporal/spatial resolution impeded evaluation whether sedentarization was synchronous, in some degree, with the amelioration of dry conditions recorded during the Late Holocene at millennial timescales. The present paper thus aims (1) to reconstruct the past environmental and climatic dynamics in the CAD (22°S) during the late Holocene at millennial to sub-centennial scales based on the pollen record of fossil rodent middens of Cuesta Chita site and; (2) to discuss their possible relationship to changes in cultivation and water management as seen at the archaeological sites of Topaín, Paniri and Turi, located in the Salado River basin. The CCH rodent midden pollen record reflects wetter (drier) than present phases around 4400, 3650, 3000, 2200–2100, 1600, 855–840, 520–450 and 100 cal yrs BP (980, 450-115 cal yrs BP). By the time that wetter-than-present conditions occurred in the CAD (Formative Period, 3500-1050 cal yrs BP), local communities had already developed small-scale horticultural practices, yet they did not develop extensive or intensive agricultural practices. Indeed, historical processes leading to economic transformations and the rapid adoption of intensive agriculture throughout the CAD after 1000 cal yrs BP occurred and were probably favored by wetter than present conditions, suggesting positive correlations between climatic and cultural change. However, these correlations are complex and non-deterministic. In fact, decreased moisture between 650 and 600 cal yrs BP in the Turi Basin was met by agropastoralists at Topaín with complex local strategies that included changing water management practices and significantly extending farmed lands. Similarly, the Topaín fields were abandoned during a period of much-wetter-than-present conditions. The chronologically fine-grained comparison of the CCH and archaeological records reveals that the relationship between climate and culture is complex, non-deterministic, and historically contingent, with examples of agricultural expansion during a time of water stress, and the abandonment of fields during a time of abundance. • Human-environment dynamics in the Central Atacama Desert during the Late Holocene. • Late Holocene climatic variability at millennial to sub-centennial resolution based on pollen records. • Wet (dry) phases occurred ∼4400, 3650, 3000, 2200-2100, 1600, 855-840, 520-450 and 100 (980, 450-115) cal yrs BP. • Human responses to climatic change are various and there is no simple relationship between water availability and land use. [ABSTRACT FROM AUTHOR]

• Identify ancient flood events, which may be the reason for decline of the culture. • Pollen and heavy metals can be used to reflect the strength of human activities. • Pollen and heavy metals revealed the process of culture from prosperity to decline. • This paper defined the chronology from prosperity to decline of Shijiahe culture. • Climate change has been revealed by pollen and heavy metals since 4800 cal. yr BP. The Shijiahe Culture (ca. 4800–4100 yr BP), which originated in the middle Yangtze Basin, was a milestone of prehistoric Chinese civilization. To reveal the interactions between climatic changes and human activities during this time interval, the geochronology and multiple proxies (pollen and heavy metals) of samples from a 220-cm-deep outer wall at the Sanfangwan Site (a typical site of the Shijiahe Culture) were analyzed. Radiocarbon dating indicates that the age range of the Sanfangwan Site is ca. 4800 to 4100 cal. yr BP. From ca. 4800 to 4600 cal. yr BP (the early Shijiahe Culture), pollen assemblages were dominated by Gramineae and an anthropogenic plant community (e.g. Ranunculaceae, Chenopodiaceae, Labiatae, and Cruciferae), indicating an expansion in rice agriculture during this interval. High metal concentrations in the same interval indicate a large flux of metals from smelting and farming activities. Between ca. 4600 and 4100 cal. yr BP (the middle and late Shijiahe Culture), decreases in Gramineae and anthropogenic pollen mirrored the recession of farming. Concurrent decreases in heavy metals may be attributable to a decline in the smelting industry. Three episodes of high pollen concentrations and visible increases in hygrophyte pollen, Pinus pollen, and fern spores at 4600–4550, 4450–4350, and 4200–4100 cal. yr BP probably indicate the occurrence of several flooding events during the middle and late Shijiahe Culture, resulting in the migration of local inhabitants. This study highlights the driving effect of flood events on the collapse of the Shijiahe Culture. [ABSTRACT FROM AUTHOR]

The Tarvagatai Nuruu National Park, situated in the northern Khangai Mountains in central Mongolia, is dominated by a forest-steppe ecosystem. An extreme continental and semi-arid climate is characteristic for forest-steppe ecosystems in Central Asia and their vegetation is very sensitive to climatic changes and human impacts by pastoralism and tree-logging. In the selected study area, nowadays human impact is exceptionally low, and it has potentially also been in the past. The focus of this paper was to reconstruct vegetation variability, climate dynamics, intensity of human impact and fire dynamics by applying a broad multi-proxy approach on a lacustrine sediment core from a small closed lake in the study area. The analyses include reconstructions of pollen, spores, non-pollen palynomorphs, and charcoal distribution as well as XRF-scanning. Overall, the radiocarbon-dated lacustrine sediment core reveals stable, long-term environmental conditions since the early Holocene (9570 cal yr BP). Palynological results indicate that vegetation varies on a comparably low level. We assume that nomadic pastoralism played a tangential role on the vegetation changes in the study area. Higher values of coprophilous fungi between 9570 and 8350 cal yr BP suggest the highest wildlife activity during the early Holocene. Hence, our multi-proxy data reveal a surprisingly stable vegetation composition and only slight climatic changes in north-central Mongolia for the entire Holocene. An initial moist and warm period from 9570 to 4180 cal yr BP was followed by a period of slightly drier and potentially cooler conditions from 4180 until 430 cal yr BP. The latest period from 430 cal yr BP to present was moist and warm. Fires were in general relatively rare except from a strong phase of fire activity between 3550 and 2960 cal yr BP. • A new multi-proxy record (pollen, NPPs, macro charcoal, XRF-data) from north-central Mongolia. • Detailed high-resolution Holocene palaeoecological record covering the last 9600 cal yr BP. • Reconstructed stable vegetation reflects limited human impact on the vegetation dynamics since the Early Holocene. • Values of coprophilous fungal spores during the early Holocene provide a baseline of wildlife activities. • Extensive fire episode from 3550 to 2960 cal yr BP. [ABSTRACT FROM AUTHOR]

Improved studies of past vegetation change are required to better understand the variation of alpine ecosystems on the Qinghai-Tibetan Plateau (QTP) in response to future climate change. Spatial and temporal variations of past vegetation can be traced by fossil pollen data mapping. In this paper, we synthesized 57 continuous pollen records on the QTP covering the past 15 kyr to depict large-scale vegetation change and its response to climate variations. In order to minimize potential chronological biases, age-depth models were revised using a state-of-the-art and consistent method for all the records. The spatial and temporal variation of major pollen taxa were examined based on interpolated pollen maps at 1000-year intervals. The arboreal pollen (AP, mainly of Pinus , Betula and Abies / Picea) content expressed significant climate signals over a broad spatial and temporal gradient. During the late glacial period, high proportions of AP widely occurred in regions that are presently unforested owing to the sparse local vegetation coverage. For the Holocene period, AP showed relatively high contributions in records from the southeastern margin of the QTP, with a decreasing gradient in abundance towards the northwest. The transportation of AP to unforested regions corresponds closely to the intensity of monsoon wind, which can be used to track the Holocene evolution of the summer monsoon. The dominant shrub and herbaceous taxa (including Artemisia , Chenopodiaceae, Cyperaceae, Poaceae and Ephedra) generally represent developments of local vegetation responding to climate variations. In addition, the persistent increase in Poaceae pollen during the mid to late Holocene correlates possibly to regional human activities. The inferred spatial and temporal patterns of major pollen types on the QTP provide significant knowledge about long-term vegetation change and its potential response to climate variations. • An initial plateau-scale examination of fossil pollen records on the Tibetan Plateau. • Spatial and temporal patterns of major pollen types were mapped at 1000-year interval. • Arboreal pollen from unforested plateau surface represents intensity of summer monsoon. • Herbaceous pollen reveals local vegetation development in response to climate change. [ABSTRACT FROM AUTHOR]

• Deltaic Holocene vegetation changes & its dynamic relation with climate & sea level. • Paucity of pollen in early Holocene succession related to low sea-level. • Higher mid-Holocene precipitations (SWM & NEM) inferred from tropical pollen signal. • Pollen record shows high NEM precipitation from ~5163 to ~2541 YBP. • Post-2541 YBP: a drier signal linked to salinity changes and river avulsion. Palynological and other sedimentary records in the south-eastern peninsular India where the retreating (North-East) monsoon brings the main rainfall are scarce. This paper tries to address not only this gap in data but also the methodological challenges of interpreting such data in terms of sea level, depositional environment and climatic changes of the area going back nearly 11040 years. In addition to other (chemical) proxies studied previously, pollen data of a chronologically well constrained sediment core (~20 m) from Porayar (11°01.178′N 79°50.446′E), in the coastal marginal part of the Cauvery delta, Southern India, have been analyzed. The three major pollen zones observed since 11,040 years are presented and discussed, as are the methodological challenges of interpreting the vegetation record in such a dynamic and diverse environment (the delta plains of southern India). The zones observed indicate various transitions: from a lower sea level condition to a more stable sea level that created an estuarine environment filled with brackish water that supported pollen assemblages of a marshland but not a true mangrove. Concurrently, pollen assemblages that indicate catchments at multiple spatial scales – local to regional, extending from the North-East monsoon dominated delta to the Western Ghats is also inferred for climate interpretation. [ABSTRACT FROM AUTHOR]

The apparently regular and favourable climate that characterizes the Holocene as an interglacial period shows, however, important climatic instability well documented in the Northern Hemisphere. These fluctuations from colder to warmer or wetter to drier affected both biodiversity and human societies in the last 12,000 years, although the impact in Southern America is still poorly known. We are here investigating the biodiversity of small mammal faunas, more sensitive to climatic changes than large mammals, combining taphonomic and palaeoecological data in the Argentine Pampas to better understand the global nature and effect of these Holocene climatic fluctuations. This paper is pioneering applying in this region palaeoecological methodologies practised in European sites, such as the chorotype classification and biomes overlap analyses. The Pampean Region is an ecotone with a confluence of three climatic regions where any change in climatic conditions should be easily detected. Our results, based on the palaeoecological requirements of small mammals, do not indicate severe changes, and most of the sites show climatic stability except for one of them, in which a possible trend towards present conditions (temperate/humid) can be inferred. • New palaeoecological methodologies are applied to the Pampean Region. • Microfauna is the best climatic indicator if multiproxy interpretations are considered. • Cave vs. open-air sites influence the composition of fossil small mammal assemblages. • Human activities in the past can distort palaeoecological interpretations. • Noticeable climatic events in the Northern hemisphere are soften/absent in the South. [ABSTRACT FROM AUTHOR]

This paper illustrates long-term trends in human population and climate from the Late Pleistocene to the Late Holocene (14,000–2500 cal. yr. BP) in order to assess to what degree climate change impacted human societies in the Near East. It draws on a large corpus of archaeo-demographic data, including anthropogenic radiocarbon dates (n = 10,653) and archaeological site survey (n = 22,533), and 16 hydro-climatic records from cave speleothems and lake sediments. Where possible, inferred population dynamics and climatic trends have been made spatially congruent, and their relationships have been statistically tested. Demographic proxies and palaeoclimatic records have been compared for the greater Near East as a whole and for seven major geo-cultural regions (Anatolia, Arabia, Cyprus, Iran, Levant, Mesopotamia, and South Caucasus). This approach allows us to identify regionalised patterns in population and climate trends. The results suggest a clear relationship between population and climate in the Late Pleistocene and Early Holocene (14,000–8326 cal. yr. BP) with population increasing in concomitance with wetter climatic conditions. During the Middle Holocene (8326-4200 cal. yr. BP) there is an increased regionalisation of demographic patterns, followed by marked interregional contrasts in the Late Holocene (4200-2500 cal. yr. BP). We identify a decoupling of demographic and climatic trends from the Middle Holocene onwards, and relate this to the existence of more complex societies. These were less vulnerable to gradual climatic shifts due to their logistical infrastructure, social organisation and technological capacity. We also assess the impact of five Rapid Climate Changes (RCC) which occurred during the study period on population levels. Although all five RCC (the so-called 10.2 k, 9.2 k, 8.2 k, 4.2 k, and 3.2 k cal. yr. BP events) are visible to some degree in our palaeoclimatic and demographic proxies, there are marked regional variations in magnitude and duration. • Modelling regional demographic trends with archaeological proxies. • Long-term trends in human population and climate from the Late Pleistocene to the Late Holocene (14,000–2500 cal. yr. BP). • Regionalised patterns in population and climate trends. • Decoupling of demographic and climatic trends from the second half of the Middle Holocene (∼5500 cal. yr. BP). [ABSTRACT FROM AUTHOR]

• Holocene vegetation history was reconstructed in a mountain area of north China by pollen data. • Mountain forests responded more sensitively to temperature before 6.0 cal. kyr BP. • Mountain forests responded more sensitively to summer monsoon after 6.0 cal. kyr BP. • Human impact was not serious for vegetation until several centuries ago. Understanding Holocene vegetation response regimes will improve predictions of future vegetation dynamics in mountain areas of semi-arid north China. In this paper, we statistically analyzed the relationship between a pollen record in a mountain area of semi-arid north China and influencing variables independent of pollen data, in the hope that potential vegetation forcing and response regimes can be explored. Our result suggests that the cool deciduous forest (CDF) at high elevation and the temperate deciduous forest (TDF) at middle and lower elevation were sensitive in responding to temperature before 6000 cal. yr BP, but were not sensitive to the summer monsoon (SM). Since 6000 cal. yr BP, the CDF and TDF were sensitive in responding to the SM instead of temperature. Hence, a shift of response regimes can be placed at ∼6000 cal. yr BP, which happened to be consistent with the time that forest expansion changed to deforestation. The insensitive response to the SM during the early Holocene might be attributed to the vegetation elevational movement, the topographic barrier for forest migration from refugia, and/or the topographically related high resistance and resilience of mountain forests. The sensitive response of CDF and TDF to the weakening SM since 6000 cal. yr BP was mainly caused by the cumulative moisture deficit caused by the continual weakening of the SM. Human activity had little impact on mountain forests until several centuries ago. Mountain forest expansion in response to climate warming during the early to middle Holocene can provide analogues for the prediction of forest dynamics of future warming. [ABSTRACT FROM AUTHOR]